The present invention relates to a rubber composition for coating a carcass cord for coating the reinforcing cord of carcass and a carcass cord coated thereby.
Tire cords such as a steel cord are used at tire parts such as carcass, as a cord reinforcing the tire parts. However, since the reinforcing cord and the tire parts are easily peeled by running, higher adhesion strength to the reinforcing cord is required in the rubber composition for coating a carcass cord.
In order to improve the adhesive property between the reinforcing cord and tire parts, comprising large amounts of sulfur for the tire parts can be used. But, since free sulfur cuts sulfur crosslinking between rubber chains, and rubber main chains by using large amounts of sulfur, the tire parts are easily broken and there has been a problem that locally large tensile deformation is generated in the reinforcing cord at running on unpaved road surface and at running after storing tires in wet environment.
Also, Japanese Unexamined Patent Publication No. 2004-217817 discloses a rubber composition comprising a compound capable of donating a methylene group and a resin comprising resorcin (refer to the Japanese Unexamined Patent Publication No. 2004-217817). But when the rubber composition is used for coating carcass cord, the adhesive property between the carcass cord and the rubber composition is insufficient and there have been problems that the rubber composition generates heat or generates cracking.